Pigmented inks and coatings, after being applied to substrates and cured, are preferably desired to cure effectively and have good cured film properties, such as hardness etc. However, some properties of, or ingredients in, the curable, pigmented inks and coatings themselves may actually hinder the ability of the inks and coatings to exhibit good cured film properties.
For example, in order for curable inks and coatings to be applied to substrates, they usually have relatively low viscosity before they are cured. In order to meet this low viscosity requirement, for example, in ink jettable inks, high levels of monoacrylates are usually included. The high level of monoacrylates, however, makes it harder to achieve good cured film properties.
For another example, in inks and some coatings, the presence of the pigment particles makes it difficult to penetrate the inks and coatings with the radiation that is necessary to cure the inks and coatings. This may result in poor cured film properties, such as the ink or coating being tacky or easily marred. Attempts have been made to allow better penetration of inks and coatings by radiation for curing purposes by including high levels of diluents and/or conventional dispersants in the inks and coating suspensions that disperse or spread out the pigment particles. Diluents are used to reduce the concentration of an ink or coating to achieve a desirable or beneficial effect. Conventional dispersants, generally, are used to stabilize pigment-containing ink or coating dispersions to prevent agglomeration or flocculation of the pigment particles and consequent settling of the pigment particles out of the dispersions. High levels of diluents and/or conventional dispersants in inks or coatings that may be necessary to disperse or spread out the pigment particles, however, tend to act as plasticizers and, therefore, contribute to poor cured film properties.
Thus, a need exists for pigmented inks and coatings, wherein the pigment is well dispersed, that after being applied to substrates and cured, have good cured film properties, such as non-tackiness and mar-resistance.